Under the leadership of T. C. Tai,the modern Chinese America-trained library pioneer,the Tsinghua College Library established the first Reference Section in China. On the basis of both Chinese and English historical materials,the paper makes a critical survey of how Tai got to know about reference work,when the Reference Section of the Tsinghua College Library was established, how its names and functions changed, and what measures in detail it once took. It is pointed out that despite the unfavorable conditions, the Tsinghua College Library played a pioneering role in the modern Chinese reference work,trying its best to enlarge its collections,provide guidance for readers,and launch inter-library loan service together with other libraries in Peking as well.